Kohlschütter-Tönz syndrome in siblings without ROGDI mutation.

BACKGROUND: Kohlschütter-Tönz syndrome is a rare neurodegenerative disorder presenting with intractable seizures, developmental regression, and characteristic hypoplastic dental enamel indicative of amelogenesis imperfecta. Recently, mutations in ROGDI were identified in part of Kohlschütter-Tönz syndrome cases, but the siblings reported here do not have a mutation in the ROGDI gene, showing that there is genetic heterogeneity in Kohlschütter-Tönz syndrome. AIM: Report two siblings that have Kohlschütter-Tönz syndrome. CONCLUSION: Early onset of seizures and lack of the ability to walk without support may be signs of non-ROGDI mutations in Kohlschütter-Tönz syndrome patients.